Multiparty Session Types and their Applications to Large Distributed - PowerPoint PPT Presentation

Multiparty Session Types and their Applications to Large Distributed Systems Nobuko Yoshida Imperial College London 1

In collaboration with: Matthew Arrott (OOI) Gary Brown (Red Hat) Stephen Henrie (OOI) Bippin Makoond (Cognizant) Michael Meisinger (OOI) Matthew Rawlings (ISO TC68 WG4/5) Alexis Richardson (RabbitMQ/VMware) Steve Ross-Talbot (Cognizant) and all our academic colleagues Laura Bocchi, Tzu-Chun Chen, Romain Demangeon, Pierre-Malo Deniel´ ou, Luca Fossati, Dimitrios Kouzapas, Rumyana Neykova, Nicholas Ng, Weizhen Yang 2

Outline ➤ Background ➤ Multiparty Session Types [POPL’08] ➤ Scribble and Applications to a Large-scale Cyberinfrastructure ➤ Monitoring Theory ➤ Summary 3

Communication is Ubiquitous ➤ Internet, the WWW, Cloud Computing, the next-generation manycore chips, message-passing parallel computations, large-scale cyberinfrastructure for e-Science. ➤ The way to organise software is increasingly based on communications. ➤ Applications need structured series of communications. ➤ Question ➣ How to formally abstract/specify/implement/control communications? 4

Communication is Ubiquitous ➤ Internet, the WWW, Cloud Computing, the next-generation manycore chips, message-passing parallel computations, large-scale cyberinfrastructure for e-Science. ➤ The way to organise software is increasingly based on communications. ➤ Applications need structured series of communications. ➤ Question ➣ How to formally abstract/specify/implement/control communications? 5

Communication is Ubiquitous ➤ Internet, the WWW, Cloud Computing, the next-generation manycore chips, message-passing parallel computations, large-scale cyberinfrastructure for e-Science . ➤ The way to organise software is increasingly based on communications. ➤ Applications need structured series of communications. ➤ Question = ⇒ Multiparty session type theory ➣ How to formally abstract/specify/implement/control communications? 6

Ocean Observatories Initiative ➤ A NSF project (400M$, 5 Years) to build a cyberinfrastructure for observing oceans around US and beyond. ➤ Real-time sensor data constantly coming from both off-shore and on-shore (e.g. buoys, submarines, under-water cameras, satellites), transmitted via high-speed networks. 7

Ocean Observatories Initiative 8

Challenges ➤ The need to specify, catalogue, program, implement and manage multiparty message passing protocols . ➤ Communication assurance ➣ Correct message ordering and synchronisation ➣ Deadlock-freedom, progress and liveness ➣ Dynamic message monitoring and recovery ➣ Logical constraints on message values ➤ Shared and used over a long-term period (e.g. 30 years in OOI). 9

Why Multiparty Session Types? ➤ Robin Milner (2002): Types are the leaven of computer programming; they make it digestible . = ⇒ Can describe communication protocols as types = ⇒ Can be materialised as new communications programming languages and tool chains . ➤ Scalable automatic verifications (deadlock-freedom, safety and liveness) without state-space explosion problems ( polynomial time complexity ). ➤ Extendable to logical verifications and flexible dynamic monitoring . 10

Dialogue between Industry and Academia Binary Session Types [PARL’94, ESOP’98] ⇓ Milner, Honda and Yoshida joined W3C WS-CDL (2002) ⇓ Formalisation of W3C WS-CDL [ESOP’07] ⇓ Scribble at Technology 11

Dr Gary Brown (Pi4 Tech) in 2007

Dialogue between Industry and Academia Binary Session Types [PARL’94, ESOP’98] ⇓ Milner, Honda and Yoshida joined W3C WS-CDL (2002) ⇓ Formalisation of W3C WS-CDL [ESOP’07] ⇓ Scribble at Technology ⇓ Multiparty Session Types [POPL’08] ⇓ 12

Dialogue between Industry and Academia Binary Session Types [PARL’94, ESOP’98] ⇓ Milner, Honda and Yoshida joined W3C WS-CDL (2002) ⇓ Formalisation of W3C WS-CDL [ESOP’07] ⇓ Scribble at Technology ⇓ Multiparty Session Types [POPL’08] ⇓ 13

� � � � Multiparty Session Types Alice → Bob : � Nat � . Global G Types Bob → Carol : � Nat � . end � � � Projection � � ���� ���� ���� ���� � ���� ���� � � � � � � � � � T Bob = ? � Alice , Nat � ; Local Types T Alice T Bob T Carol ! � Carol , Nat � ; end Type checking � P Bob = s ? ( Alice , x ) ; Multiple Python BPEL Java Languages s ! � Carol , x � ;0 14

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Multiparty Session Type Theory ➤ Multiparty Asynchronous Session Types [POPL’08] ➤ Progress ➣ Global Progress in Dynamically Interleaved Multiparty Sessions [CONCUR’08] , [Math. Struct. Comp. Sci.] ➣ Inference of Progress Typing [Coordination’13] ➤ Asynchronous Optimisations and Resource Analysis ➣ Global Principal Typing in Partially Commutative Asynchronous Sessions [ESOP’09] ➣ Higher-Order Pi-Calculus [TLCA’07,TLCA’09] ➣ Buffered Communication Analysis in Distributed Multiparty Sessions [CONCUR’10] 18

➤ Logics ➣ Design-by-Contract for Distributed Multiparty Interactions [CONCUR’10] ➣ Specifying Stateful Asynchronous Properties for Distributed Programs [CONCUR’12] ➣ Multiparty, Multi-session Logic [TGC’12] ➤ Extensions of Multiparty Session Types ➣ Multiparty Symmetric Sum Types [Express’10] ➣ Parameterised Multiparty Session Types [FoSSaCs’10, LMCS] ➣ Global Escape in Multiparty Sessions [FSTTCS’10] [Math. Struct. Comp. Sci.] ➣ Dynamic Multirole Session Types [POPL’11] ➣ Nested Multiparty Sessions [CONCUR’12] 19

➤ Dynamic Monitoring ➣ Asynchronous Distributed Monitoring for Multiparty Session Enforcement [TGC’11] ➣ Monitoring Networks through Multiparty Sessions [FORTE’13] ➤ Automata Theories ➣ Multiparty Session Automata [ESOP’12] ➣ Synthesis in Communicating Automata [ICALP’13] ➤ Typed Behavioural Theories ➣ On Asynchronous Eventful Session Semantics [FORTE’11] [Math. Struct. Comp. Sci.] ➣ Governed Session Semantics [CONCUR’13] ➤ Choreography Languages ➣ Compositional Choreographies [CONCUR’13] 20

Language and Implementations ➤ Carrying out large-scale experiences with OOI, VMWare, Red Hat, Congnizant, UNIFI, TrustCare ➣ JBoss S CRIBBLE [ICDCIT’10, COB’12] and S AVARA projects ➤ High-performance computing Session Java [ECOOP’08,ECOOP’10,Coordination’11] = ⇒ Multiparty Session C [TOOLS’12][Hearts’12][EuroMPI’12] ➤ Multiparty session languages Ocaml, Java, C, Python, Scala, Jolie ➣ Trustworthy Pervasive Healthcare Services via Multiparty Session Types [FHIES’12] ➣ SPY: Local Verification of Global Protocols [RV’13] ➣ Practical interruptible conversations: Distributed dynamic verification with session types and Python [RV’13] 21

Session Type Projects ➤ COST Action Behavioural Types for Reliable Large-Scale Software Systems , over 60 academic members in 17 countries ➤ SADEA EPSRC Exploiting Parallelism through Type Transformations for Hybrid Manycore Systems , with Vanderbauwhede, Scholz, Gay and Luk ➤ Programme Grant From Data Types to Session Types: A Basis for Concurrency and Distribution , with Wadler and Gay ➤ EPSRC Conversation-Based Governance for Distributed Systems by Multiparty Session Types ➤ NSF Ocean Observatories Initiative ➤ VMware Dynamic Assurance based on Multiparty Session Types ➤ Cognizant EPSRC Knowledge Transfer Secondments 22

Session Type Reading List ➤ [ESOP’98] Honda, Vasconcelos and Kubo, Language Primitives and Type Disciplines for Structured Communication-based Programming, ➤ [SecRet’06] Yoshida and Vasconcelos, Language Primitives and Type Disciplines for Structured Communication-based Programming Revisited, ENTCS. ➤ [ECOOP’08] Hu, Yoshida and Honda, Session-Based Distributed Programming in Java ➤ [POPL’08] Carbone, Yoshida and Honda, Multiparty Asynchronous Session Types ➤ [WS-FM’09] Dezani-Ciancaglini and de’Liguoro, Sessions and Session Types ➤ [TOOLS’12] Ng, Yoshida and Honda, Multiparty Session C ➤ [CONCUR’10] Caires and Pfenning, Session Types as Intuitionistic Linear Propositions; [ICFP’12] Walker, as Classical Linear Propositions. ➤ [OOI] Video by John Orcutt, Professor of Geophysics, UCSD, Ocean Observing: Oceanography in the 21st Century 23

A rare cluster of qualities From the team of OOI CI: Kohei has lead us deep into the nature of communication and processing. His esthetics, precision and enthusiasm for our mutual pursuit of formal Session (Conversation) Types and specifically for our OOI collaboration to realize this vision in very concrete terms were, as penned by Henry James, lessons in seeing the nuances of both beauty and craft, through a rare cluster of qualities - curiosity, patience and perception; all at the perfect pitch of passion and expression. 24